Air India Express flight from Dubai veers off taxiway at Mangaluru Airport

The current physical distancing guidelines provided by the World Health Organisation (WHO) and by the US Centers for Disease Control and Prevention (CDC) may not be adequate to curb the coronavirus spread, according to a research which says the gas cloud from a cough or sneeze may help virus particles travel up to 8 metres. The research, published in the Journal of the American Medical Association, noted that the the current guidelines issued by the WHO and CDC are based on outdated models from the 1930s of how gas clouds from a cough, sneeze, or exhalation spread.

Study author, MIT associate professor Lydia Bourouiba, warned that droplets of all sizes can travel 23 to 27 feet, or 7-8 metres, carrying the pathogen.

According to Bourouiba, the current guidelines are based on "arbitrary" assumptions of droplet size, "overly simplified", and "may limit the effectiveness of the proposed interventions" against the deadly pandemic.

 She explained that the old guidelines assume droplets to be one of two categories, small or large, taking short-range semi-ballistic trajectories when a person exhales, coughs, or sneezes.

However based on more recent discoveries, the MIT scientist said, sneezes and coughs are made of a puff cloud that carries ambient air, transporting within it clusters of droplets of a wide range of sizes.

Bourouiba warned that this puff cloud, with ambient air entrapped in it, can offer the droplets moisture and warmth that can prevent it from evaporation in the outer environment.

"The locally moist and warm atmosphere within the turbulent gas cloud allows the contained droplets to evade evaporation for much longer than occurs with isolated droplets," she said.

"Under these conditions, the lifetime of a droplet could be considerably extended by a factor of up to 1000, from a fraction of a second to minutes," the researcher explained in the study.

The MIT scientist, who has researched the dynamics of coughs and sneezes for years, added that these droplets settle along the trajectory of a cough or sneeze contaminating surfaces, with their residues staying suspended in the air for hours.

"Even when maximum containment policies were enforced, the rapid international spread of COVID-19 suggests that using arbitrary droplet size cutoffs may not accurately reflect what actually occurs with respiratory emissions, possibly contributing to the ineffectiveness of some procedures used to limit the spread of respiratory disease," Bourouiba wrote in the study

Jan 2: A year after 12,000 acres of forests in Bandipur went up in smoke, the Karnataka Forest Department is gearing up for the summer even as the Forest Survey of India (FSI) has cautioned that 22.78 lakh acres (9,222 sq km) or about 20% of the green cover spread across three districts in the central part of the state is fire-prone.

The FSI studied forest fire incidents across the country between 2004-05 and 2017 before coming up with state-specific inputs.

According to the 13-year observation, Karnataka has 7,352 “fire points” or areas measuring 5 km X 5 km with frequent fire incidents.

Though the number is lower compared to states like Maharashtra, Madhya Pradesh and Odisha with over 20,000 points, the sheer spread of the fire-prone area itself is a challenge for the Karnataka Forest Department.

According to data, about three lakh acres (1,199.9 sq km) of forest area is very highly fire prone with 26 to 52 fire incidents in 13 years. This is followed by 7.6 lakh acres (3,067 sq km) of “highly fire prone” areas with an average of one to two incidents every year.

Almost all of the “red alert” areas are concentrated in Uttara Kannada, Chikkmagaluru, Shivamogga and Chamarajanagar districts. As temperature rises at the end of January, so does the risk of forest fires, requiring officials to be on vigil till the end of summer.

After an investigation into the Bandipur blaze revealed that faulty fire lines and poor supervision were the reason for the spread of the fire, the department has come up with a multi-pronged approach to prevent similar incidents this year.

“After the Bandipur incident, we have created a fire cell and a standard operating procedure (SOP) which everyone has to follow. Firstly, a fire management plan is prepared and approved by a competent authority.

The SOP has well defined firelines which have to be executed by December-end and burning must be completed by January 15,”  Principal Chief Conservator of Forests (Head of Forest Force) Punati Sridhar told DH.

He said that to ensure its strict implementation, GPS readings of firelines are to be submitted for random verification.

“All the required equipment from fire jackets to shoes, gloves, backpack sprayers and tractors mounted with 2,000-5,000 litre tanks with high pressure pumps will be deployed at vantage points,” he said.

In addition, the department’s fire cell works in collaboration with the Karnataka State Remote Sensing Applications Centre (KSRSAC) to give fire alerts within half and hour of an area catching fire and detected by satellites.

“Earlier, the gap used to be four hours by when the fire would have spread beyond control. Now, with reduced time gap, it would be easier to control fire early,” he added.

Mangaluru, Mar 30: Police on Monday registered a case against a man, who, after return from Dubai, had failed to adhere to lockdown guidelines of house quarantine.

The case was filed by Assistant Commissioner, Puttur, Dr Yathish Ullal.

The man, who returned from Dubai on March 21, had a seal on his hand and was supposed to stay at home for 14 days, but was seen roaming around the city, hence he was taken into custody and a case registered.